>>>>> "Matthew" == Matthew Walton <[EMAIL PROTECTED]> writes:
Matthew> So you're saying that in Perl 6 it will be entirely impossible to Matthew> determine if / appears as the division operator or as the beginning of Matthew> a regex from a purely syntactic examination of the source code? Yes. Matthew> I'm finding that very, very hard to believe. Regexps aren't valid Matthew> where /-the-operator is, after all. And that's precisely why Perl can work as it does. If an operator is expected, / is divide. If a term is expected, / is the beginning of a regex. This has been true since Perl1 (maybe 0). There are a few other characters that also work similarly, but / is the most frequent and most troublesome. And it got worse for Perl5, because of user-defined prototypes, which as far as I can tell, are still present in Perl6. Matthew> Please correct me if I'm wrong, but I've got the impression that Perl Matthew> 6 is tokenisable without requiring BEGIN blocks to be run - provided Matthew> no grammars which the tokeniser doesn't already know about are used, Matthew> of course, that one will never be avoidable. Your impression is wrong. In the presence of user-defined prototypes, you *must* execute the code that might alter a prototype in order to determine whether / is a divide (and therefore standalone token) or the beginning of a regex (and therefore must locate the end of the regex to properly be a token). Please see the referenced perlmonks article. All the handwaving in the world won't fix this. As long as we have dual-natured characters like /, and user-defined prototypes, Perl cannot be lexed without also parsing, and therefore without also running BEGIN blocks. -- Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095 <[EMAIL PROTECTED]> <URL:http://www.stonehenge.com/merlyn/> Perl/Unix/security consulting, Technical writing, Comedy, etc. etc. See PerlTraining.Stonehenge.com for onsite and open-enrollment Perl training!
